Methine dyes containing a pyrimidazolone group



Patented July 11 1 950 METHINE DYES CONTAINING A PYRINHDAZOLONE GROUPEdward Bowes Knott, Harrow Wealdstone, England, assignor to EastmanKodak Company, Rochester, N. Y., a corporation of New Jersey N Drawing.Application December 29, 1948, Se-

rial No. 68,091. In Great Britain January 23,

16 Claims. (01. zen-240.2)

This invention relates to the manufacture of dyes, particularly dyes foruse in photographic materials.

As is well known, in order to make a photographic emulsion sensitive tolight of a wide range of wavelengths, it is necessary to add asensitizing dye or mixture of sensitizing dyes to the emulsion. Dyesused in current practice, however, have the disadvantage that they arenot always wholly removable by washing from the emulsion after .it hasbeen exposed, and consequently a faint but permanent stain remains,which is often objectionable, especially when the emulsion is coated onpaper.

Dyes are also used in photographic materials in filter or antihalationlayers. In these cases, the dye should be capable of being destroyed orbleached out easily. Among .the dyes proposed for this purpose are theoxonol dyes, which contain the following structure:

where n represents 0 or a small integer, and X and Y represent the atomsnecessary to complete cyclic systems which may be the same or different.The structure may also be represented as where n, X and Y have the samemeanings as before.

I have now found a new class of dyes, some of which can be used asnon-staining, sensitizing dyes, and some of which can be used as filterdyes, or can be incorporated in antihalation layers. My new dyes aredistinguished in that they contain a pyrimidazolone (2-keto-2,3-dihydropyrimidazole) nucleus, i. e. the nucleus which can berepresented by the following formula:

This nucleus is linked through a methine or polymethine chain, attachedto the 3-carbon atom of the pyrimidazolone nucleus, to various nuclei,suchas another pyrimidazole nucleus (oxonol dye) or a heterocyclic basicnucleus, e. g. pyridine,

quinoline, benzoxazole, thiazoline, benzothiazole, etc. (merocyaninedye) It is, therefore, an object of my invention to provide new methineand polymethine dyes containing a pyrimidazolone group and methods forpreparing these dyes. Another object is to provide methine andpolymethine dyes containing a pyrimidazolone nucleus which are useful insensitizing photographic silver-halide emulsions. Still another objectis to provide photographic silverhalide emulsions containing these newdyes. A still further object is to provide new methine and polymethinedyes containing a pyrimidazolone group which are useful as filter dyesand in the preparation of antihalation layers. Another object is toprovide photographic elements comprising 'these new dyes. Other objectswill become apparent from a consideration of the following descriptionand examples.

The methine or polymethine dyes of my invention containing apyrimidazolone group can be represented by the following two generalformulas:

ethyl, n-propyl, isopropyl, n-butyl, isobutyl, etc. groups (e. g. analkyl group of the formula wherein n is a positive integer from 1 to 4),L represents a methine group (both substituted and unsubstituted), Arepresents the non-metallic atoms necessary to complete a heterocyclicnucleus of the pyridine series, Z represents the nonmetallic atomsnecessary to complete a heterocyclic nucleus containing from 5 to 6atoms in the heterocyclic ring, such as those of the thiazole series (e.'g. thiazole, 4-methylthiazole, 4-(2-thienyl) thiazole,4-phenylthiazole, etc. nuclei), the benzothiazole series (e. g.benzothiazole, 5-ch1orobenzothiazole, etc. nuclei), the naphthothiazoleseries (e. g. -naphthothiazole, fi-naphthothiazole, etc. nuclei), thebenzoxazole series (e. g. benzoxazole, etc. nuclei), the naphthoxazoleseries (e. g. a-naphthoxazole, p-naphthoxazole, etc. nuclei),

dride, n-butyric anhydride. etc.

3 the selenazo-le series (e. g. 4-methylselenazole, 4- phenylselenazole,etc. nuclei) the benzoselenazole series (e. g. benzoselenazole,5-chlorobenzoselenazole, etc. nuclei), the naphthoselenazole series (e.g. a-naphthoselenazole, fi-naphthoselenazole, etc., nuclei), thethiazoline series (e. g. thiazoline, etc. nuclei), the3,3-dialkylindolenine series (e. g, 3,3-dimethylindolenine, etc.nuclei), the benzimidazole series (e. g. 1,3-dimethylbenairnidazole,

1,3-diethylbenzimidazole, etc. nuclei), the. py r,i'

dine series (e. g. pyridine, hydropyridine, etc. nuclei), the quinolineseries (e. g. quinoline, -6- ethoxyquinoline, G-methylquinoline, etc.nuclei), etc, and d and n each represents a positive integer from 1 to2.

The methine dyes of my invention represented by Formula, I above canconveniently be prepared by condensing a cyclammonium quaternary saltcontaining in the aor y-position a substituent selected from the groupconsisting of fi-arylaminovinyl and 5 -arylamino A butadienyl groups, e.g. a cyclammonium quaternary salt selected from those represented by thefollowing general formula:

wherein R, Z, n and d have the values set forth above, X represents ananion, e. g. Cl, 1*, Br-, SCN, C1041 CHIICOQ, E).-CH3C6H4-SO3 CsH5 SOs,CHrZOSDs", CzHsOSOr, etc., R3 represents an aryl group, e. g. a phenyl,a diphenyl, a xylyl or a naphthyl (a or B) group (e. g. an aryl groupcontaining from 6. to 12 carbon atoms), R4 represents a hydrogen atom oran acyl group of a carboxylic acid, such as acetyl, propionyl, benzoyl,etc. groups (especially an acyl group of an aliphatic carboxylic acid),with an alkali metal salt form or an acid addition salt Of apyrimidazolone compound represented by the following general formula:

wherein A has the value set forth above. The

compounds represented by Formula III can be,

readily obtained by reacting a quaternary salt selected from thoserepresented by the following general formula:

. the presence or absence of a carboxylic acid an:

hydride, e. g. acetic anhydride, propionic anhy- The condensation ofquaternary salts with a diaryl formamidine (e. g. diphenylformamidine)in the presence or absence of a, carboxylic acid anhydride e. g. aceticanhydride) is described in detail in British Patent 344,409, acceptedMarch 4, 1931. A similar method is outlined in White et al, U. S. Patent2,263,749, dated November 25, 1941, wherein other compounds representedby Formula VI are reacted with various quaternary salts. The concomitantor subsequent acylation of such reaction products is also described inthe White et al. patent.

Typical cyclammonium quaternary salts represented by Formula III above,include, for example, 2-(p-acetanilidovinyl) -quinoline ethiodide,Z-(fiaeetanilidovinyl).benzoxazole ethiodide, 2- S-acetanilidovinyl)thiazoline ethiodide, 2- (B-acetanilidovinyl) -benzothiazole ethiodide,Z-(fi-acetanilidovinyhpyridine methiodide,4-(fl-acetani1idovinyDpyridine ethiodide, 2-(6-acetanilido-AbutadienyDbenzoazole ethiodide, 2-(fi-acetanilidovinyl) benzoselenazoleethiodide, l-(t-anilino- A -butadienyl)benzothiazole ethiodide and itst-anilino-y-bromo-n -butadienyl analogues, 2- (B acetanilidovinyl) 1,3diethylbenzimidazolium iodide, etc.

Some of the dyes represented by Formula I', either in the form of thefree bases or their quaternized derivatives, have. been found to beespecially useful as non-staining, strongly sensitizing dyes inphotographic materials. The free base of some of the dyes of Formula Iwhere d equals 2, unlike analogous dyes containing an acidic nucleus asth keto nucleus, have been found to be stable toward.- the usualdevelopers. However, quaternization of these dyes, as hereinafterdescribed, gives a product which can be easily bleached by the usualphotographic materials.

As noted above, the. pyri'midazolones represented by Formula IV are usedin the form of their alkali metal (e. g. sodium, potassium, etc.) saltsor acid addition salts. The acid addition salts represented by thefollowing formula:

wherein A has the value set forth above and X1 represents a halogen.atom (e. g. achlorine atom, a bromine atom, etc.) have been found to beespecially useful, owing to their greater stability.

Pyrimidazolone hydrochloride or hydrochromide may be prepared accordingto the methods of Chichibabin. (Ber.,,1924-, 57B, 2092-) either bytreating Z-imino-1,2-dihydropyridine 1 acetic acid with concentratedmineral acids, or by. heating 2-l'ialogenoacetam-idopytidine, forexample, 2- bromoacetamidopyridine, in a suitablesolvent such as nebutylalcohol. Sodium pyrimidazolone may be prepared by the methodsof Reindel-(Ben, 1924,5713, 1381). I

The methine dyesof invention; represented by Formula II canadvantageously be prepared by condensing an alkali metal salt form oracid addition salt (i. e. the compounds of Formula VII) of one of thepyrimidazolone compounds represented by Formula IV with one of compoundsselected from those represented by Formula VI, in the presence orabsence of a carboxylic acid anhydride, e. g. acetic anhydride,propionic anhydride, n-butyric anhydride, etc.

Typical compounds represented: by Formula VI includefl-ethoxyacraldehyde diet-hyl acetal; ,6- anilinoacraldehyde anil,o-anilinog lutaconic aldehyde anil, ,B-anilino a-halogenoacraldehydeanils (e.v g. 3-anilino-aebromoacraldehyde, anil, manilaino-a-chloroacraldehyde anil, or their hydrochlorides; etc),alkyl-B-anilinoacraldehyde anils wherein d has the values set forthabove, have been found to have unusual properties in that they are notbleached bynor mal" developing agents. These dyes are alsostable, andcan be used as fabric'dye's with thehelp of' a mordant. The dyesrepresented'by Formula VIII can ,easily be quaternized, and it'has beenfound that, where d equals 2 in the" above formula-the quaternized dyesare bleached by'the usual developing agents. On the other hand,quaternization of the dye represented by Formula VIIIwhere d equals 1"",does not give a product which can 'be'bleached by the usual developingagents. Quaternization of the dyes of Formula VIII, where 1! equals 2,gives dyes which can be represented by the following general formulazwherein X has the values setv forth above, and R6 represents an alkylgroup, e. g. methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl,benzyl, etc. groups.

Other dyes represented by Formula II which I have found to be especiallyuseful include those represented by the following general formula:

wherein Q represents a halogen atom (e. g. a chlorine atom, a bromineatom, etc.) or an alkyl group (e. g; a .methyl group).. Where Qrepresents a halogen atom, the dyes are not bleached by the usualdeveloping agents, although these dyes can be quaternized to give a dyewhich can be so bleached. The dyes represented by Formula X, where Qrepresents an alkyl group, such as a methyl group, can be bleached bythe ordinary photographicdeveloping agents. 1 I

The manufacture of the dyes of my invention either by the condensationof the compounds of Formula III with an alkali metal salt form oracidaddition salt ofthose of Formula IV to give the dyes of Formula I,or the condensation of an alkali metal salt form or acid addition saltof a compound of Formula IV with those of Formula VI to give the dyes ofFormula II can advantageously be carried out in the presence of a basiccondensing agent, i. e. an acid binding agent, e. g. the trialkylamines,such as triethylamine, tri n propylamine, triisopropylamine, trinbutylamine, etc., heterocyclicamines, such as 8 N alkylpiperidines, ag. N-methyl.- and N-ethyl piperidine; etc. Alkali metalsalts ofcarb'oxylic acids, e. g. sodium acetate, etc. are also useful. Alkalimetal carbonates. e. g. sodium carbonate can also be used as anacid-binding agent in my invention. Heat accelerates the condensations,and temperatures varying from about 25 C. to the reflux temperature ofthe reactants can be used. The condensations can also be carried out inthe presence or absence of an inert diluent, if desired. Typicaldiluents include, for example, the lower aliphatic alcohols (e. g.One-to four carbon atoms) ,such as ethyl, isop'ropyl, n-propyl,n-butyl,- etc. alcohols, pyridine, -benzene,- etc. The diluent shouldbeinert toward thedyes formed, and is advantageously chosen so that thedye formed will-separate therefrom at least upon cooling the reactionmixture. i i H v The followingexamples will serve to illustrate morefully the manner whereby I practicemy invention."

Example 1 2- (1 -ethylquinoli'1te) l 3py'rimi dazolone)dimethin-emerocyanine 4.9 grams of 2-p-acetanilidovinylquinolineethiodide, 2.15 grams of pyrimidazolone hydrobromide, cc. of ethanol,and 2 cc. of triethylamine were refluxedtogether for two minutes; J'Oncooling, the hydrobromide .of the requireddye separated as goldencrystals, M. P. 300 C. The crystals were filtered off and boiled uptwice with ethanol in which they were sparingly soluble. The salt wasthen dissolved in alcoholic triethyl: amine by heating, and water addedwhich pre; cipitated the dyein a crystalline form. Thecrystals werecollected on a filter, dried, dissolvedin hot ethanol, and ether addedslowly until. crys tallization commenced. On slow cooling, the dye(base) was, obtained as needles with a green reflex, M. P. 268 C.(decompJ. It sensitized a silver bromiodideemulsion with a maximum at580m J" Example 2.-[ 2-' (3-ethylbenzomazole) l (3-minutidazolone)dimethinemerocyanine O='C- ':'-N

4.34 grams of 2-p-acetanilidovinylbenzoxazole ethiodide, 2.15 grams ofpyrimidazolone hydrobromide, 25 cc. of ethanol, and 2.8 cc. oftriethylamine were. refluxed together for 30 minutes, and the solutionconcentrated to half volume and allowed to I stand overnight.- Thehydrobromide 'of 'the required dye crystallizedan'd was filtred off, andthen recrystallized fromethanol in the form' of. red needles, M. P. 2020., This salt strongly sensitized a:silver chloride emulsion with amaximum at530 m The base was pre-: paredfromthesalt by the methods:described-in Exampl .11. f m ng orange c ystals, M. BR26919- smart off.It was then dissolved in ethanol and a few drops :of.ay40% acetic acidsolution of hydrogen bromide added. On cooling, the hydrobromideseparated as orange rosettes, M. P. 236 C. -It sensitized a silverchloride emulsion strongly with a maximum at 550"m';1.f

Example 4.-[2( 3 ethylbenzothiazole) 1-(3-p11- rimidazolone)dimethinemeroeyanine 4.5 grams of i 2-p-acetanilidovinylbenzothiazoleethiodide, 2.15 grams of pyrimida'zolone hydrobromide, 25 cc. ofethanol, and 2.8 cc. of triethylaminewere refluxed together for 30minutes, and the solution then concentrated to half-volume. Crystalsprecipitated on chilling, whichwere collected and dissolved in ethanolwith the addition of "triethylamine, 'The'addition of an aqueous sodiumcarbonate-solution precipitated the dye Example 5.-'[2-(3ethylbenzothiazolw (31JJ- rim'idazolone) dimethinem'erocyanine 4.5.grams of '2 3 acetanilidovinylbenzothiazole ethiodide, 1.65 grams-ofsodiumpyrimidazolone and '25 cc. of ethanoliwere refluxed together for30' minutes; and then" the alcohol distilled off. 100 cc. of water wereadded to the remainder, and the mixture heated on the steam bath untilthe-dye crystallized. 1 It was collectdaftercool:

inepdriea and recrystallized fromethanol-ether,

. 8"- forming'*purfilefneedlesorgreen crystals, M. P.

Example =6 .-'E2-(1-ethyZquinoZine)l-(3pyrimidazolone)dimethinemerocyanine 4.9 grams "of '12,8;acetanilidovinylquinoline ethiodide, 1.6 I gramspf jsodiumpyrimidazolone, and cc. o'fethanol' were refluxed together for30'minutes, and wate'r added to precipitate the dye (basel,it'Iwas'collected, washed with water, dried andrecrystalli'zedfromethanol-ether f r n needles M-.- 3- 68-C-,,I E mpze 7[2-'(1'.-inetliylpyridihe) ](3-pyrimi- I dazolone) dimethinemerocyanine3.5 grams of Z-B-anilinovinylpyridine methiodide were refluxed with 15cc. of acetic anhydride for 15 minutes, the solution chilled and theacetyld'e'r'ivative'precipitatedwith ether, and the ether decanted01f.137 grams or pyrimidazolone hydrochlo'r'ide; l.6"gram's' of sodiumacetate, and 25 cc. of ethanol added, and the mixture refluxed for 30minutefsi The alcohol was then distilled oil; and the .residuedissolwdin hot water and the solutionchilled. The dye (base) precipitated andwas collected and recrystallized from hot water forming purple needles,M. P. 245 C. It sensitized a silver chloride emulsion strongly with amaximum at 550 m Example '8. 4 (l-ethylpyridine) l- (3-pyrimidazolone)dimethinemerocyamne r. :-0=Ol |l {Lon-or t h N/ \CH maximumat560=myiExample 9. [2- (3-ethylbenzoxazole) l- (Ii-pyrimidazolone)tetramethinemerocyanine lected and recrystallized from. ethanol as darkbrassy crystals, P. 300" C. It showed absorption maxima of 585 m l'(water) and 600 m/L (alcohol).

Example 10.-}3,3-bispyrlmidazolonetrimethineoronol t (Loam-01kt ii HO/ I\CH HA\ ylH ink ji 2 grams of pyrimid'azolone' hydrochloride, 1' gram offi-ethoxyacraldehyde .diethyl acetal, 20 cc. of ethanohand 2 cc.of'triethylamine were refluxed together for 30 minutes. 'The'triethylamine can be omitted, if desired. The dye (salt) was collectedafter cooling, and dissolving in boiling water containing an excess oftriethylamine. Impurities were removed by filtration, and the bluesolution concentrated under reduced pressure. As the triethylamineboiled off, the dye (base) precipitated in the form of purple needles,M. P. 284 C. The yield was 1.9 grams, and the dye showed a maximumabsorption in methanol Of 600 Ill 1,.

1 gram of dye was quaternized by fusing with 2 grams of methylp-toluenesulfonate for 20 minutes at 110 C. The resultant solid wasboiled up with benzene, filtered oil, andboiled with acetone givingbrightgreen, water-soluble crystals, which showed absorption maxima ofv595 m (Water),

and 585m (methanol) v Example 11 3,3 -'-bis-pyrimidazolonepentameth- 2.4grams 'of pyrimidazolone hydrochloride, 2.8 grams of t-anilinoglutaconicaldehyde anil hydrochloride, 40 CCIOf ethanol, and 8.4 cc. oftriethylamine were shaken together at room temperature for 15 minutes,"and then heated-on-a steambath, for 30 minutes. 2.45 grams of thedyelhydrochloride) "were obtained on cooling; as green'crys tals, M.P.218 C. (decompJf' The salt was heated and stirred with aqueous 2 Nsodium carbonate to give green needles of the base, which were washedwith water, alcohol and ether. The dye showed a maximum absorption of590 mp. (methanol).

The dye Was quaternized by fusing 1.1 grains thereof with 2.5 grams ofmethyl p-toluenesulfonate for 15 minutes at 110 C. The resultant solidwas boiled up with benzene to give 2.4 grams of green crystals (100%yield). It was recrystallized from methanol forming bright greencrystals, M. P. 269 C. It showed absorption maxima of 658 m (water) and685 mp (methanol);

Aqueous potassium iodide or bromide can be added to an aqueous solutionof the quaterniz'ed: dye to give the methohalides, which are lesssoluble. I

The dye was also quaternized by fusing 1 molecular equivalent thereofwith 4 molecular equivalents of ethyl p-toluenesulfonate for 30' minutesat 120 C. to give the etho-p-to1uenesulfonate. This is more soluble thanthe meth0-p-t0luenesulfonate. The ethiodide and ethobromide can also beformed by the methods described above for the methiodide andmethobromide, and are sparingly soluble in water.

Example 1 2 .3,3" -bis-pyrimidazolonemesometl yltrimethineoxonol NC-OH0=ON l salami l HO N H: N H H I 1.35 grams of pyrimidazolonehydrochloride, 1.1

Example 1 3.3,3 -bis-pyrimidazolohemesochloro- 3.4 grams ofpyrimidazolone hydrochloride; 2.6 grams of a-chloro-pani1inoacraldehydeanil, 30 cc. of ethanol and 45 cc. of aqueous 2 N sodium carbonate wereheated together on a steam bath for 20 minutes. The dyecrystallizedduring this, time, and was collected and boiled up withethanol, when 2.7 grams yield) of dye were obtained as'purple crystals,M. P. 300 C. The dye was water-soluble and showed absorption 'max-ima'of 592 my (water) and 602 m (m'ethanoll.

The dye was quaternized by fusing" 1.7 grams thereof with 4 grams ofmethyl p-toluenesulf on'ate' for 20 minutes at 120 C. The resultantsolidwas boiled up with benzene giving 2.1 *grams of the methop-toluenesulfonate yield of "the mono-quaternary salt), as a steel 'greypowden M. P. 300 C. which was decomposedbypro longed boiling inmethanol. It showed absorption maxima (methanol) at 590 my (water) an,fiooirn 11 Example14.3,3'r-bis-pyrimidazolonemesobromotrimethineozvonol 3.4 grams ofpyrimidazolone hydrochloride, 3 grams of a-bromo-fl-anilinoacraldehydeanil and 30 cc. of ethanol were heated until no solid matter remained,45 cc. of aqueous 2 N sodium carbonate added, and the whole heated on asteam bath for 20 minutes.

The dye was collected after cooling and washed with alcohol and water.

0.5 gram of the dye was quaternized by fusing with 1.8 grams of methylp-toluenesulfonate at 120 C. for 20 minutes. The resultant solid wasboiled up with benzene and recrystallized from ethanol, forming bronzecrystals, M. P. 300 C. the quaternized dye showed absorption maxima of587 m (water) and 600 m (methanol). 7

In a manner similar to that illustrated in the above examples, otherdyes coming within the scope of my invention can be prepared. Forexample, by replacing the S-acetanilido compounds of Examples 1 to 8 bya molecularly equivalent amount of 2- (dacetaniljdovinyl)benzoselenazole ethiodide, [2-(3 ethylbenzoselenazole) l-(3pyrimidazolone) dimethinemerocyanine can be ob-- tained. Similarlyreplacing the B-acetanilido compound of Example 1 with a, molecularlyequivalent amount of 2-(6-acetani-lidovinyl)benzothi azole methiodidegives [2-(3-methyl-ben zothiazole)l (3pyrimidazolone)dimethinemerocyanine. The pyridine nucleus of thepyrimidazolone dyes of my invention can be substituted by variousgroups, e. g. Cl, Br, OH, CH3, C2H5, etc.

The sensitivity of photographic silver-halide emulsions can be alteredby many of the dyes of cording to the type of light-sensitive salt whichgoes to make up the emulsion and according to the effects desired. Thesuitable and most economical concentration for any given emulsion willbe apparent to those skilled in the art,- upon makingthe ordinar testsand observations, nus-- tomarily used in-the art of emulsion-making. To

prepare a gelatino-silver -halide emulsion, the following procedure issatisfactoryr-A quantity of the dye is dissolved in methyl alcohol and avolume of this solution (which may be diluted with water) containingfrom 5 to 100 mg. of dye is slowlyadded to about 1000 cc. of agelatino-silverhalide emulsion with stirring. Stirring is continueduntil the dye is uniforml i-and practically homogeneously dispersed.With the more powerful of these new sensitizing dyes to 20 mg. of dyeper 1000 cc. of emulsion sufiice to produce the maximum sensitizingeffect with the ordinary The dyes are advantagelatino silver-halideemulsions. The. above statements are only illustrative: and not to beunderstood as limiting my invention in anysense, as it will be apparentthat these dyes canb'e. in; corporated by other methods in many of thep'hotographic emulsions customarily employed in'the art, such forinstance as by bathing the plate or film, upon which the emulsion hasbeen coated, in a solution of the dye in an appropriate solvent,although such a method is ordinarily not to be preferred. The claimsareintended to cover any combination of these new dyes with aphotographic silver salt emulsion whereby the dye exerts a sensitizingeife'ct upon the emulsions as Well as a photographic element comprisinga support, ordinarily transparent, upon which the light-sensitiveemulsion is coated or spread and permitted to set or dry. v

For the preparation of overcoating. layers, filter layers, and,antihalation layers embodying. the dyes of my invention (especiallythose of the oXonol and merocyanine series), according to thisinvention, from 50 mg. to mg. of dye are dissolved in from 2 to 5 vcc.of a water-miscible solvent. Methanol or acetone are suitable for thispurpose, but pyridine or l3-ethoxyethanol (Cellosol-ve) can be also beused; The solution is then added to about 25 cc. of'a' 5 per centgelatin solution at. 40 C. andthe mixture coated on the support. l I

As noted above, some of the dyes of this invention can also beadvantageously used as coloring matters for textiles, particularlycellulose acetate, silk, or the like.

What I claim as my invention and desire secured by Letters Patent of theUnited States is:

1. A methine dye selected from the group consisting of those representedby the following :two general formulas:

wherein R represents an alkyl group, L represents a methine group, Arepresents the non.-

' metallic atoms necessary to complete a pyridine wherein R represents.a primary alkyl group of the formula CnH2n+l wherein n represents apositive integer from 1 to 4, (1 represents a positive integer from 1 to2.12 represents the non-5 iera l3 metallic atoms necessary to complete aheterocyclic nucleus of the thiaz oline series, and A represents thenon-metallic atoms necessary to complete a heterocyclic nucleus of J thepyridine series.

3. A merocyanine dye selectedfromthose represented by the followinggeneral formula:

O=CN R-1 I --o= oH-o11)l=t wherein R represents a primary alkyl group ofthe formula CnH2n+1 wherein n represents a positive integer from 1 to 4,d represents a positive integer from 1 to 2, Z representsthe-non-metallic atoms necessary to complete a heterocyclic nucleus ofthe benzoxazole series, and A represents the non-metallic atomsnecessary to complete a heterocyclic nucleus of the pyridine series.

5. A merocyanine dye selected from those represented by the followinggeneral formula:

wherein R represents a primary alkyl group of the formula CnH2n+lwherein n represents a positive integer from 1 to 4, 11 represents apositive integer from 1 to 2, Z represents the nonmetallic atomsnecessary to complete a heterocyclic nucleus of the quinoline series,and A represents the non-metallic atoms necessary to complete aheterocyclic nucleus of the pyridine eries.

6. The merocyanine dye represented by the formula:

H in

H:CS

7. The merocyanine dye represented by the formula:

it v

ii] 8. The merocyanine dye reprejseri tedby'j th formula: I I

9. The merocyanine dye represented by the formula:

10. A process for preparing a merocyanine dye comprising condensing a,cyclammonium quaternary salt, containing in a position selected from thegroup consisting of the aand y-positions, a reactive group selected fromthe group consisting of a 2-arylamino-vinyl group and a4-ary1amino-1,3-butadienyl group, with a member selected from the groupconsisting of acid addition salts and alkali metal salt forms of acompound selected from those represented by the following generalformula:

,wherein A represents the non-metallic atoms necessary to complete apyridine nucleus.

11. A process for preparing a merocyanine dye comprising condensing az-arylaminovinylthiazoline quaternary salt with an acid addition salt ofa compound selected from those represented by the following generalformula:

wherein A represents the non-metallic atoms necessary to complete aheterocyclic nucleus of the pyridine series.

12. A process for preparing a merocyanine dye comprising condensing aZ-aryiaminovinylbenzothiazole quaternary salt with an acid addition saltof a compound selected from those represented by the following generalformula:

at t

i I wherein A represents the non-metallic atoms necessary to complete a,heterocyclic nucleus of the pyridine series.

13. A process for preparing a merocyanine dye comprising condensing a2-arylaminovinylbenzoxazole quaternary salt with an acid addition saltof a compound selected from those represented by the following generalformula:

75 wherein A represents the non-metallic atoms necmums l5 essarytqycomplete a heterocyclic nucleus of the pyridine series. 7

14. A process for preparing a merocyanine dye comprising condensing a2-arylaminovinylquinoline quaternary salt with an acid addition salt ofa 5 compound selected from those represented by the following. generalformula:

wherein A represents .thenon-metallic atoms necessary tocomplete,a..heterocyc1ic nucleus of the pyridine series and ldrepresents a positive integer from. 1 to 2. v .1 I v 1 16. The oxonoldye represented by the formula:

EDWARD BOWES KNOTT.

No references cited.

Certificate of Correction Patent No. 2,514,649 July 11, 1950 EDWARDBOWES KNOTT It is hereby certified that error appears in the printedspecification of the above numbered patent requiring correction asfollows:

Column 3, lines 26, 27, and 28, for that portion of the formula readingRI N read N \R4 \R column 3, line 55, in the formula, for CHL C read0H),, =C'; column 4, line 17, for benzoazole read benzoxazole; column 7,line 29, for CI-1:011 read CH- CH; column 8, first formula therein, forCH, read 0 H same formula, upper right hand portion thereof, for

N N a read 5 line 27, for the incorrectly printed letter over fl read N;column 13, lines 26 to 30 mcluslve, strike out the formula and insertinstead the following:

and that the said Letters Patent should be read as corrected above, sothat the same may conform to the record of the case in the PatentOfiice.

Signed and sealed thls 24th da; of October, A. D. 1950.

THOMAS F. MURPHY,

Assistant Commissioner of Patents.

1. A METHINE DYE SELECTED FROM THE GROUP CONSISTING OF THOSE REPRESENTEDBY THE FOLLOWING TWO GENERAL FORMULAS: